Earlier quoted context omitted.
the team owns the code. the whole team. whoever is oncall gets to wake up at 3am if there is an issue.
What happens when you have 2M or 20M lines of code floating around? Is every engineer expected to know enough to fix (or at least patch) any issue at 3 am?
As unrealistic as it sound, yes, if you're oncall you need to be able to understand the problem and fix it/mitigate it at 3am. This opens another can of worms around what is worth of a 3am page and how development, deployment and monitoring should be done but if you wake me up I should be empowered to do something about it